Radiofrequency ablation and chemotherapy versus chemotherapy alone for locally advanced pancreatic cancer (PELICAN): study protocol for a randomized controlled trial

Background

Approximately 80% of patients with locally advanced pancreatic cancer (LAPC) are treated with chemotherapy, of whom approximately 10% undergo a resection. Cohort studies investigating local tumor ablation with radiofrequency ablation (RFA) have reported a promising overall survival of 26–34 months when given in a multimodal setting. However, randomized controlled trials (RCTs) investigating the effect of RFA in combination with chemotherapy in patients with LAPC are lacking.

Methods

The “Pancreatic Locally Advanced Unresectable Cancer Ablation” (PELICAN) trial is an international multicenter superiority RCT, initiated by the Dutch Pancreatic Cancer Group (DPCG). All patients with LAPC according to DPCG criteria, who start with FOLFIRINOX or (nab-paclitaxel/)gemcitabine, are screened for eligibility. Restaging is performed after completion of four cycles of FOLFIRINOX or two cycles of (nab-paclitaxel/)gemcitabine (i.e., 2 months of treatment), and the results are assessed within a nationwide online expert panel. Eligible patients with RECIST stable disease or objective response, in whom resection is not feasible, are randomized to RFA followed by chemotherapy or chemotherapy alone. In total, 228 patients will be included in 16 centers in The Netherlands and four other European centers. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, RECIST response, CA 19.9 and CEA response, toxicity, quality of life, pain, costs, and immunomodulatory effects of RFA.

Discussion

The PELICAN RCT aims to assess whether the combination of chemotherapy and RFA improves the overall survival when compared to chemotherapy alone, in patients with LAPC with no progression of disease following 2 months of systemic treatment.

Trial registration

Dutch Trial RegistryNL4997. Registered on December 29, 2015. ClinicalTrials.govNCT03690323. Retrospectively registered on October 1, 2018

Long-Term Functional Recovery of Hepatocytes after Cryopreservation in a Three-Dimensional Culture Configuration

Hepatocyte cryopreservation is essential to ensure a ready supply of cells for use in transplantation or as part of an extracorporeal liver assist device to provide on-demand liver support. To date, most of the work on hepatocyte cryopreservation has been performed on isolated hepatocytes, and has generally yielded cells which display low viability and greatly reduced short-term function. This report presents the development of a freezing procedure for hepatocytes cultured in a sandwich configuration. A specially designed freezing unit was used to provide controlled temperatures throughout the freeze-thaw cycle. Cooling rate, warming rate, and final freezing temperature were evaluated as to their effect on hepatocyte function as judged by albumin secretion. Under optimized conditions (cooling at 5°C/min and warming at ≥400°C/min), freezing to −40°C resulted in full recovery of albumin secretion within 2-3 days post-freezing, whereafter albumin secretion levels remained normal for the duration of the experiments (2 wks). Freezing to −80°C lead to an approximate 70% recovery of long-term protein secretion when compared to control cultures. In addition, the overall hepatocyte morphology as judged by light microscopy, closely followed the functional results. The sandwich culture configuration, thus, enables hepatocytes to maintain a satisfactory level of long-term protein secretion after a freeze-thaw cycle under optimized conditions, and offers an attractive tool for further studies into the mechanisms of freezing injury and subsequent hepatocellular recovery. These results are a promising step in the development of satisfactory storage procedures for hepatocytes.

Collagen-rich stroma in aggressive colon tumors induces mesenchymal gene expression and tumor cell invasion

Gene expression-based classification systems have identified an aggressive colon cancer subtype with mesenchymal features, possibly reflecting epithelial-to-mesenchymal transition (EMT) of tumor cells. However, stromal fibroblasts contribute extensively to the mesenchymal phenotype of aggressive colon tumors, challenging the notion of tumor EMT. To separately study the neoplastic and stromal compartments of colon tumors, we have generated a stroma gene filter (SGF). Comparative analysis of stroma^high and stroma^low tumors shows that the neoplastic cells in stroma^high tumors express specific EMT drivers (ZEB2, TWIST1, TWIST2) and that 98% of differentially expressed genes are strongly correlated with them. Analysis of differential gene expression between mesenchymal and epithelial cancer cell lines revealed that hepatocyte nuclear factor 4α (HNF4α), a transcriptional activator of intestinal (epithelial) differentiation, and its target genes are highly expressed in epithelial cancer cell lines. However, mesenchymal-type cancer cell lines expressed only part of the mesenchymal genes expressed by tumor-derived neoplastic cells, suggesting that external cues were lacking. We found that collagen-I dominates the extracellular matrix in aggressive colon cancer. Mimicking the tumor microenvironment by replacing laminin-rich Matrigel with collagen-I was sufficient to induce tumor-specific mesenchymal gene expression, suppression of HNF4α and its target genes, and collective tumor cell invasion of patient-derived colon tumor organoids. The data connect collagen-rich stroma to mesenchymal gene expression in neoplastic cells and to collective tumor cell invasion. Targeting the tumor-collagen interface may therefore be explored as a novel strategy in the treatment of aggressive colon cancer.

Peroperative measurement of PTH in the management of primary hyperparathyroidism

This study was performed to prospectively evaluate the efficacy of a newly developed, non-expensive and non-commercial perioperative PTH-assay as indicator of successful surgery in minimally invasive adenomectomy (MIA) for primary hyperparathyroidism (pHPT).

METHODS

A chemoluminescence-based PTH-assay was modified to significantly shorten the incubation time, producing results in a total of 45-60 minutes. Its reliability was tested in 19 patients undergoing MIA for pHPT. Patients were selected for MIA based on preoperative imaging including ultrasound and CT. After verification of its reliability, the PTH assay was incorporated into our treatment protocol and its results registered and correlated with serum calcium levels and surgical outcome.

RESULTS

The PTH assay was found to fully correlate with the current gold standard, i.e. serum calcium levels on the first postoperative day after MIA. It was subsequently used in 55 patients selected for MIA, as well as in 26 patients undergoing conventional neck exploration (CNE). In all cases it correctly indicated surgical failure/success. The conventional re-exploration that was required in 3 patients after unsuccessful MIA, was also correctly interpreted on the basis of the PTH-assay. In 2 cases an unexpected delay was encountered in the decline of PTH-levels following adenomectomy.

CONCLUSION

The perioperative PTH-assay described is a reliable, inexpensive, and relatively fast predictor of surgical outcome, and should be considered essential for minimally invasive surgery in patients with pHPT.

Angiostatin inhibits pathological but not physiological retinal angiogenesis

PURPOSE

Antiangiogenic treatment is a promising new therapy for angiogenesis-dependent diseases. In the current study, the biologic effects on pathologic and physiological angiogenesis in the retina of angiostatin, a very potent angiogenesis inhibitor were determined. In addition, the effects of angiostatin on the growth and development of newborn mice were examined.

METHODS

Oxygen-induced retinopathy was induced by subjecting mice postnatal day (P)7 to hyperoxic conditions (5 days) followed by normoxic conditions (relative hypoxia). Mice were treated with angiostatin (intravitreal or systemic). Retinal blood vessels were visualized by fluorescein angiography. Retinal neovascularization was assessed by counting intravitreal endothelial cell nuclei. Growth and organogenesis were determined between P0 and P14.

RESULTS

Relative hypoxia resulted in intravitreal proliferation of retinal blood vessels. However, proliferation was inhibited completely by systemic administration of angiostatin without affecting normal retinal vascularization. After intravitreal injection of angiostatin, pathologic proliferation of the retinal blood vessels was impaired by 62%. Neither systemic nor intravitreal treatment impaired the development or growth of organs throughout the body.

CONCLUSIONS

Angiostatin inhibits oxygen-induced intravitreal pathologic retinal angiogenesis without affecting the development of physiological retinal vascularization, development, and growth of newborn mice. Therefore, antiangiogenic treatment may be a useful tool in the treatment of proliferative retinopathies.

Risk factors for cancellation of stereotactic large core needle biopsy on a prone biopsy table

Among patients undergoing stereotactic needle biopsy of the breast on a prone biopsy table, a substantial proportion of planned procedures are terminated prematurely. This study was undertaken to identify risk factors for cancellation of these procedures and to derive a clinical rule for predicting cancellation. Risk factors for cancellation were assessed in a group of 476 consecutive patients with non-palpable lesions planned for large core needle biopsy. 64 (13%) of these planned procedures were cancelled. Multivariate regression analysis was applied to identify independent risk factors for cancellation. Validation took place by applying the logistic rule on a validation set, including 5 cancelled and 35 successful biopsy procedures. Mammograms that were difficult to interpret owing to extremely dense breast tissue, axillary location of the non-palpable lesion, body mass index below 20, less than 15 mm distance from the lesion to the chest wall or the presence of more than one non-palpable lesion were identified as independent risk factors. The logistic rule discriminated patients with successful and cancelled biopsy procedures with a receiver operator characteristic (ROC) area of 0.72. In the validation set, the area under the ROC curve was 0.92. The prediction rule, based on mammographic and clinical findings, discriminated patients with successful and cancelled needle biopsy procedures to a certain extent. The risk of cancellation of the stereotacic biopsy procedure is considerable in cases of very dense breast tissue or the presence of multiple risk factors.

Cost comparison between stereotactic large-core-needle biopsy versus surgical excision biopsy in The Netherlands

Yearly, approximately 7200 Dutch women with non-palpable breast lesions are referred for a diagnostic surgical excision biopsy. Recently, less invasive alternatives such as stereotactic large-core-needle biopsy have emerged. The aim of this study was to compare the costs of surgical excision biopsy and large-core-needle biopsy. As stereotactic equipment is expensive, the costs of large-core-needle biopsy depend on the extent of centralisation of this facility. Therefore, we assessed the extent of economies of scale in four different scenarios of (de)centralisation. We collected cost data in five Dutch hospitals. The cost of surgical excision biopsy amounted to 1184 Euros. In cases where large-core-needle biopsy would be employed decentralised in all 114 hospitals in The Netherlands, the average costs were estimated to be 1186 Euros compared with 572 Euros in a centralised scenario with involvement of 10 hospitals. Therefore, centralisation of stereotactic equipment for core-needle biopsies would be advisable from an economic perspective.

[Diagnostics in clinically occult, radiologically suspect breast lesions more often surgery than needle diagnostics with image monitoring]

OBJECTIVE

To inventory the diagnostic methods used in patients with clinically occult, radiologically suspect breast lesions.

DESIGN

Enquiry.

METHOD

The departments of radiology of all Dutch hospitals were sent a list in January 2000 containing questions concerning the number of thread localizations in 1999 and the use of cytological or histological needle diagnostics with image monitoring prior to surgical intervention in clinically occult, radiologically suspect breast lesions. Of the 120 questionnaires mailed, 74 (62%) were completed and returned by clinics throughout the country.

RESULTS

Fifty-one of the 74 hospitals (69%) had prior to operation carried out histological or cytological examinations and in these 51 hospitals this was done in 1743 of the 2857 lesions (61%): fine-needle aspiration cytology was performed in 1046 (/1743 = 60%; /4140 lesions in all 74 hospitals = 25%) and/or histological needle biopsy in 784 (45%; /4140 = 19%).

CONCLUSION

In less than half of all non-palpable breast abnormalities non-surgical methods of diagnosis are used, histological needle biopsy less often than fine needle aspiration cytology.

Hepatocyte growth factor and melanoma: gene transfer studies in human melanocytes

Hepatocyte growth factor (HGF), a fibroblast-derived protein that affects the growth, motility and differentiation of epithelial cells, is a mitogen for human melanocytes and has recently been implicated as an important factor for the development and dissemination of melanomas. To better define the possible role of HGF in the multi-step progression from melanocyte to melanoma cell, we used retrovirus-mediated gene transfer to introduce the gene encoding human HGF into normal human melanocytes, thus causing these cells to produce a growth factor they do not normally express and creating a new autocrine loop as sometimes occurs in melanoma cells. Cells were transduced with an efficiency of 6%, and the modified cells synthesized and secreted significant levels of HGF (6.6 ng/10(7) cells per 24 h) in vitro. Cells expressing HGF had a higher rate of proliferation when compared with unmodified cells and formed large, dense, melanin-positive colonies on a plastic surface. Immunostaining showed HGF-positive melanocytes with varying levels of expression, and HGF protein was detected throughout the whole cell. Although proliferation of HGF-expressing melanocytes was enhanced, they failed to form colonies in a soft agar assay. These results suggest that expression of HGF, by virtue of its ability to enhance proliferation and cell clustering, may play a role in the multi-step process of transformation, but an autocrine signal of HGF alone is not sufficient for malignant transformation.

Impact of stereotactic large-core needle biopsy on diagnosis and surgical treatment of nonpalpable breast cancer

INTRODUCTION

Stereotactic large-core needle biopsy is increasingly replacing needle-localized breast biopsy for the diagnosis of nonpalpable breast disease. In this prospective study, the impact of the introduction of this technique on diagnosis and surgical treatment of nonpalpable breast cancer was assessed in two hospitals in The Netherlands.

PATIENTS AND METHODS

A total of 84 patients with nonpalpable breast cancer, diagnosed by means of stereotactic large-core needle biopsy (needle biopsy group) were compared with 80 patients diagnosed with nonpalpable breast cancer before the introduction of large-core needle biopsy. These patients were diagnosed by means of needle-localized open breast biopsy (control group). Clinical outcome measures evaluated included: duration of diagnostic and therapeutic intervals and number of surgical procedures required for complete surgical treatment. Subgroup analysis was performed for the category of microcalcifications without tissue distortion.

RESULTS

For the needle biopsy group, the median interval between initial referral to the surgeon and the availability of histological diagnosis was 9 days and the interval between initial referral and complete surgical treatment was 31 days. These intervals were significantly longer for the control group (19 days and 44 days respectively); 75% of patients in the needle biopsy group were treated in a single step surgical procedure compared to 16% of the patients in the control group (67 vs 25% respectively for the subgroup). The mean number of surgical procedures required to complete surgical treatment was 1.31 for needle biopsy group vs 1.91 for the open biopsy group (1.46 vs 1.84 for the subgroup).

CONCLUSION

Introduction of stereotactic large-core needle biopsy leads to a reduction of the time to diagnosis and the time to complete surgical treatment of nonpalpable breast cancer. It also reduces the number of surgical procedures required for complete surgical treatment of nonpalpable breast cancer. The benefits of large-core needle biopsy may also be anticipated for patients with microcalcifications without tissue distortion.

Coagulopathy following major liver resection: the effect of rBPI21 and the role of decreased synthesis of regulating proteins by the liver

This prospective study investigated the role of reduced hepatic synthesis of regulating proteins in coagulopathy after partial hepatectomy (PH) compared with major abdominal surgery (MAS) without involvement of the liver. Furthermore, we studied the effect of rBPI21, an endotoxin-neutralizing agent, on coagulopathy after PH was studied. Compared with MAS, PH resulted in significantly elevated levels of thrombin-antithrombin-III and plasmin-alpha2-antiplasmin complexes. Levels of antithrombin-3, alpha2-antiplasmin, fibrinogen, plasminogen, alpha2-macroglobulin (alpha2-M), and C1-inhibitor remained lower following PH. Treatment with rBPI21 led to significantly lower levels of tissue-type plasminogen activator (t-PA). Post-operative disseminated intravascular coagulation (DIC) was associated with significantly higher bilirubin and t-PA plasma levels and significantly lower levels of alpha2-M. This study indicates that PH induced hepatic failure results in decreased synthesis of hepatic regulating plasma proteins and subsequent activation of coagulation and fibrinolysis. Prevention of t-PA release by rBPI21 may have important clinical implications. Decreased availability of alpha2-M may be a factor in post-operative DIC.

Major liver resection results in a changed plasma amino acid pattern as reflected by a decreased Fischer ratio which improves by bactericidal/permeability increasing protein

BACKGROUND/AIMS

Major liver resection results in a high morbidity and mortality, and endotoxin plays a role in post-resection hepatic failure. Severe hepatic failure as seen in hepatitis and cirrhosis may be accompanied by hepatic encephalopathy and is characterized by a typical plasma amino acid pattern reflected by a decreased Fischer ratio. This study was performed to evaluate the plasma amino acid pattern in patients undergoing major liver surgery receiving placebo or the endotoxin-neutralizing agent bactericidal/permeability-increasing protein (rBPI21).

PATIENTS AND METHODS

Forty-eight patients were randomized in this phase II, dose escalation, multicenter trial. Plasma amino acid profiles were determined preoperatively, and on the first (day 1) and third (day 3) postoperative day.

RESULTS

In the placebo group the Fischer ratio decreased significantly on both postoperative days. Administration of rBPI21 also resulted in a decreased Fischer ratio on day 1, but not on day 3. Highly elevated alanine plasma levels were observed on day 1 in placebo-treated patients, whereas rBPI21 prevented this elevation. Plasma alanine levels on day 1 correlated with the duration of post-resection hepatic failure.

CONCLUSIONS

Major liver resection results in a decreased Fischer ratio and a rise in plasma alanine levels. Plasma levels of alanine on the first postoperative day correlated with the duration of the post-resection hepatic failure. rBPI21 improved the Fischer ratio and prevented the rise of plasma alanine levels.

No effect of nadroparin prophylaxis in the prevention of central venous catheter (CVC)-associated thrombosis in bone marrow transplant recipients

Complications of CVCs in 382 consecutive patients receiving a stem cell transplantation (SCT) were analysed. Early complications were pneumothorax (3.6%), haematothorax (0.5%), dislocation (3%) and dysfunction (3.6%). Eighty-seven-associated infections (22%) were observed, leading to removal of the CVC in 26 patients. More bacteraemias were associated with double- or triple-lumen CVCs, 19% vs 5% in single lumen CVCs (P < 0.0001). Coagulase-negative staphylococci were the predominant microorganisms in 72%. A special point of investigation was CVC-associated thrombosis and the prophylactic value of nadroparin. Two consecutive regimens with nadroparin were used and compared; 7 days 2850 IE nadroparin and 10 days 5700 IE nadroparin. The incidence of CVC-associated thrombosis was 6.9% in 382 patients with 390 catheters. The incidence was 8% in patients receiving one of the prophylactic nadroparin regimens compared to 6% in a comparable control group without prophylaxis. A short course of nadroparin was unable to prevent thrombotic complications after discontinuation.

Role of intraoperative ultrasound of the liver with improved preoperative hepatic imaging

OBJECTIVE

To find out whether intraoperative ultrasound (IOUS) of the liver should still be considered a routine procedure for patients having hepatic resections as their preoperative investigation has become so much better with the standard use of triphasic spiral computed tomograms (CT).

DESIGN

Retrospective study.

SETTING

University medical centre, Utrecht, The Netherlands.

PATIENTS

26 consecutive patients undergoing liver resection.

MAIN OUTCOME MEASURES

How much additional information was given by IOUS, and its influence on operative strategy; how IOUS facilitated the hepatic resection.

RESULTS

IOUS revealed additional information over triphasic CT in 13/26 patients, which led to a change in the surgical procedure in 4 (15%). For all 4 patients the change in surgical approach proved to be correct as judged by histology and clinical outcome. In 12 patients IOUS facilitated the resection by providing helpful three-dimensional anatomical insight.

CONCLUSION

Despite recent improvements in preoperative investigation, IOUS should still be recommended as a routine procedure in patients having hepatic resections. In addition to aiding the ultimate decision about which part to resect, it also gives insight into the hepatic anatomy.

Direct, minimally invasive adenomectomy for primary hyperparathyroidism: An alternative to conventional neck exploration?

OBJECTIVE

To evaluate the feasibility and efficacy of a direct, minimally invasive adenomectomy (MIA) as an alternative to conventional neck exploration (CNE) in patients with primary hyperparathyroidism.

SUMMARY BACKGROUND DATA

Because primary hyperparathyroidism is caused by a solitary adenoma in 85% to 90% of patients, a direct adenomectomy through a mini-incision would theoretically suffice whenever an adenoma is correctly localized on preoperative imaging. If effective, a less invasive method could spare the patient an unnecessary bilateral neck exploration, thus saving time and rendering future surgical procedures in the neck less problematic.

METHODS

Between October 1994 and October 1998, 110 consecutive patients with biochemically proven primary hyperparathyroidism who were to undergo surgery were enrolled in this study. Ultrasound and spiral CT were routinely performed as standard preoperative imaging modalities in the first series of 65 patients. In the second series of 45 patients, ultrasound was performed as the sole initial modality; it was supplemented by CT only in case of inconclusive test results. If test results were unequivocal (one adenoma), the patient was offered MIA. CNE was performed if the results were equivocal or if multiglandular disease was suspected.

RESULTS

Overall, 84 patients were selected for MIA and 26 for CNE. In the first series, 2 MIA procedures (2/51) were converted to CNE because of negative perioperative findings. All 65 procedures resulted in normocalcemia. In the second series, all but five (4/33 MIAs, 1/12 CNEs) resulted in normocalcemia. A reexploration (CNE) was performed in three patients, resulting in normocalcemia after resection of a second or third adenoma. Two patients are still awaiting reexploration. In both series together, 78 of the 110 patients were successfully treated with MIA and spared CNE.

CONCLUSION

MIA is a safe and effective alternative to CNE that may replace CNE in approximately two thirds of all patients.

Continuous administration of angiostatin inhibits accelerated growth of colorectal liver metastases after partial hepatectomy

Human plasminogen-derived angiostatin is one of the most potent antiangiogenic agents currently known. However, it is unclear whether angiostatin is also effective against accelerated tumor growth induced by local up-regulation of growth factors, including angiogenesis stimulators, such as in regenerating liver. Prior to addressing this question, we tested, in mice, whether continuous administration of angiostatin could improve its biological effects. This assumption was based on the relatively short half-life of angiostatin in mice, as well as on the theoretical necessity to suppress tumor-induced angiogenesis continually. The findings presented here clearly indicate continuous administration to be superior to the conventional twice-daily bolus injections. Using the maximally effective regimen of 100 mg/kg/day via s.c. pump infusion, we found angiostatin to not only suppress s.c. primary tumors but also to significantly inhibit the outgrowth of colorectal hepatic metastases in resting liver and even to inhibit accelerated tumor growth in regenerating liver after 70% partial hepatectomy. In conclusion, angiostatin could play an important role in patients subjected to partial hepatectomy to prevent outgrowth of residual micrometastases, provided it is administered continuously to obtain maximal biological effects.

Diagnostic accuracy of needle-localized open breast biopsy for impalpable breast disease

BACKGROUND

Needle-localized open breast biopsy (NLBB) is considered the gold standard procedure for the diagnosis of impalpable breast disease. In an observational follow-up study the sensitivity and negative predictive value of this procedure was determined in a clinical population with long-term follow-up.

METHODS

Some 199 consecutive patients with a benign histological diagnosis on NLBB were followed for the occurrence of breast cancer, using information from the Dutch National Morbid-Anatomical Record Department. Based on a review of mammograms and histological slides, an expert panel decided whether the carcinomas detected during follow-up were newly developed, or were present already at the time of the NLBB.

RESULTS

After a median follow-up of 60.5 months, seven carcinomas were detected. At panel review, six appeared to have been missed by NLBB. The sensitivity of NLBB was 99 per cent after 2 years of follow-up, but dropped to 96 per cent after 5 years. Similarly, the negative predictive value dropped from 99 per cent after 2 years to 94 per cent after 5 years of follow-up.

CONCLUSION

NLBB is an accurate diagnostic procedure for the evaluation of impalpable breast disease. However, with longer follow-up the accuracy becomes lower than generally reported.

Diagnostic accuracy of large-core needle biopsy for nonpalpable breast disease: a meta-analysis

For the evaluation of non-palpable lesions of the breast, image-guided large-core needle biopsies are increasingly replacing needle-localized open breast biopsies. In this study, the diagnostic accuracy of this minimally invasive technique was evaluated by reviewing the available literature. Five cohort studies were included in a meta-analysis. Sensitivity rate, histological agreement between needle biopsy and subsequent surgery or long-term mammographic follow-up and clinical consequences for different disease prevalences were assessed. The sensitivity rate of large-core needle biopsy for the diagnosis of breast cancer was high (97%). The reclassified agreement rate between core biopsy and subsequent surgical biopsy or long-term mammographic follow-up was also high (94%). In case of 20% breast cancer prevalence among women referred after screening (as in the US), the risk of breast cancer despite benign large-core needle biopsy result is less than 1%. In European countries, however, prevalence of breast cancer among referred women is 60-70%. This would result in a risk of breast cancer despite benign large-core needle biopsy result of 4-6%. The results of this meta-analysis indicate that the image guided large-core needle biopsy is a promising alternative for the needle localized breast biopsy. However, additional research is needed to explore the limiting factors of the technique. Without such detailed knowledge, a benign histological diagnosis on large-core needle biopsy in countries with high prevalence of malignancy among referred women should be interpreted with caution.

Sentinel node biopsies in melanoma patients: a protocol for accurate, efficient, and cost-effective analysis by preselection for immunohistochemistry on the basis of Tyr-PCR

BACKGROUND

Immunohistochemistry (IHC) of serial sectioning is considered the gold standard for detection of melanoma activity in sentinel node (SN) biopsies. However, this is cost and labor intensive. In contrast, tyrosinase reverse transcription-polymerase chain reaction (RT-PCR) is simple and quick, but it is hampered by its extreme sensitivity. This study was performed to test whether a strategy that combines the two methods, using tyrosinase RT-PCR to preselect nodes for IHC, could be accurate and cost effective.

METHODS

In 36 patients, SNs were identified by scintigraphy and patent blue uptake. Of each SN, one cross section was analyzed first by hematoxylin and eosin staining. Next, all nodes were examined by serial sectioning and IHC of one-half and tyrosinase RT-PCR of the other. Before comparison, all results were documented in a blinded manner. Material costs and workload estimates were noted per SN.

RESULTS

Fifty-five SNs were retrieved from the 36 patients. Hematoxylin and eosin staining of the first cross section revealed tumor positivity in 3 patients (6 SN). Tyrosinase RT-PCR was positive in 11 of the remaining 33 patients (19 of 49 SN). Of these same 11 patients, only 5 were shown to have tumor-positive SNs by using IHC on serial sections (7 SN). All these nodes had been positive for tyrosinase on PCR. For IHC, an average of 40 sections were prepared and examined per SN at a cost of $200(U.S.)/SN. In contrast, routine tyrosinase RT-PCR costs $37(U.S.)/SN, and takes 5% of the time necessary for IHC. A strategy including hematoxylin and eosin staining on the first cross section, followed by tyrosinase RT-PCR on half of each negative (half) node, could preselect nodes to be taken through serial sectioning. In these series, such a strategy would have prevented serial sectioning and IHC of 30 SN from 22 patients. Apart from a considerable gain in efficiency, this would have reduced material costs by a minimum of $6000 (U.S.). This discrepancy would be even higher if work intensity of analysts and pathologists were considered.

CONCLUSIONS

In routine analysis of SN biopsies in melanoma patients, tyrosinase RT-PCR can be used effectively to preselect nodes for further IHC of serial sections. This method seems both time and cost effective.

Acute-phase response patterns in isolated hepatic perfusion with tumour necrosis factor alpha (TNF-alpha) and melphalan in patients with colorectal liver metastases

BACKGROUND

In this study, we have evaluated hepatotoxicity, secondary cytokine production and hepatic acute-phase response (APR) in patients who underwent isolated hepatic perfusion (IHP) with tumour necrosis factor (TNF) alpha and melphalan for irresectable colorectal liver metastases.

DESIGN

An extracorporeal veno-venous bypass was used to shunt blood from the lower body and intestines to the heart. Inflow catheters were placed in the hepatic artery and portal vein, and an outflow catheter in the inferior caval vein. The liver was perfused for 60 min with 0.4 mg of TNF-alpha plus 1 mg kg-1 melphalan (IHPTM group, n = 6) or 1 mg kg-1 melphalan (IHPM group, n = 3). The liver was washed with macrodex before restoring vascular continuity.

RESULTS

After the washout procedure, a TNF-alpha peak (169 +/- 38 pg mL-1) was demonstrated in the IHPTM group only. Both groups demonstrated peak levels of interleukin 6 (IL-6) in the perfusate as well as systemically. These were significantly higher in the IHPTM group. Acute-phase protein (APP) levels followed a similar pattern as has been demonstrated after major surgery, with no significant differences between both groups. The addition of TNF-alpha to the perfusate did not lead to a significant difference in APP levels and the time course between groups.

CONCLUSIONS

IHP with TNF and melphalan is followed by a transient systemic peak of TNF directly after liver washout. Secondary IL-6 induction was seen in the present study after IHP with and without TNF, which was highest when TNF was added. This phenomenon cannot be extrapolated to APP induction, which appeared unaffected by the addition of TNF, presumably because the surgical procedure itself already causes maximal stimulation of APP production.

[Peroperative parathyroid hormone assay: assurance of successful surgical treatment of primary hyperparathyroidism]

OBJECTIVE

To study the reliability and applicability of a rapid parathormone (PTH) test as predictor of successful surgical treatment of primary hyperparathyroidism.

DESIGN

Prospective.

METHOD

All 35 consecutive patients undergoing surgery for primary hyperparathyroidism in the University Hospital Utrecht, the Netherlands, in august 1997-august 1998, were tested just prior to surgery, and immediately following adenomectomy. The rapid PTH test consisted of a modification of the computerized immunometric detection by chemoluminescence. The decrease of serum PTH as estimated with the rapid test was correlated with surgical findings as well as postoperative serum calcium levels. In the first 25 patients (group A) the reliability of the test was investigated. In the next 10 patients (group B) the PTH test results were allowed to have implications for surgical management, i.e. an insufficient (< 50%) decrease of serum PTH following adenomectomy resulted in immediate re-exploration.

RESULTS

The 35 patients, 22 women and 13 men, had a median age of 58 years (range: 22-80). The results obtained with our rapid PTH test correlated fully with both conventional PTH measurement techniques and postoperative serum calcium levels. In group A 21/25 patients showed adequate (> 50%) decrease of their serum PTH levels; the 4 patients without such decrease were the ones displaying persistent postoperative hypercalcaemia. In group B 9/10 patients had adequate PTH decrease immediately following adenomectomy, while in one patient this was only attained after further exploration and excision of a second adenoma. No false-positive or false-negative measurements were encountered.

CONCLUSION

The rapid PTH test used is a reliable predictor of successful adenomectomy for primary hyperparathyroidism, also in minimally invasive surgery.

Detection of malignant breast tumours in dense breast tissue: results of 99mTc-tetrofosmin scintimammography related to surgery

AIMS

To assess the contribution of 99mTechnetium tetrofosmin (99mTc-TF) scintimammography for staging of breast lesions in patients with a suspicious or non-diagnostic mammogram to reduce unnecessary surgical procedures in future.

METHODS

Fifty patients with suspicious physical examinations and/or mammography underwent 99mTc-TF breast imaging.

RESULTS

Scintimammography with 99mTc-TF was positive in 37 patients (36 true positive, one false positive) and negative in 13 patients (12 true negative, one false negative). The detection of a malignant tumour by 99mTc-TF was independent of the density of the breast tissue. In 33 patients with a malignant breast tumour 99mTc-TF was diagnostic with respect to axillary status, but in four out of 19 patients with a histologically positive axillary lymph node status, tumour involvement remained undetected by scintigraphy. Moreover, in four patients, scintimammography revealed an additional discrete area of increased 99mTc-TF uptake, which proved to be second primary breast cancers.

CONCLUSIONS

99mTc-TF scintimammography appears to be an accurate diagnostic test in patients with a symptomatic breast lesion and a non-diagnostic mammogram, also in those patients with dense breast tissue. This procedure may also have potential for the detection of second primary breast cancers in an early stage.

Towards quality assurance of the sentinel node procedure in malignant melanoma patients: a single institution evaluation and a European survey

The status of the regional lymph node (LN) is a critical component in staging patients with malignant melanoma. Biopsy of the first tumour-draining LN (sentinel node, SN) may replace routine elective LN dissection. However, until now, the applied methods have differed widely. Therefore, the aim of this study was to formulate recommendations for the pre-operative identification and intra-operative retrieval of the SN. We present the results of an independent survey of the clinical practice of the SN procedure via a postal questionnaire among 136 nuclear physicians in different institutes throughout 16 European countries. Moreover, the results of the SN procedure in our institution in an open prospective intervention trial in 80 patients with malignant melanoma without palpable LNs are also presented. In our protocol, on average, 6 h prior to surgery, 80 MBq technetium-99m nanocolloid was injected intracutaneously around the circumference of the diagnostic excision scar of the primary melanoma. No additional blue dye procedure was used to judge the accuracy of the radioguided SN procedure on its own. For successful identification of the radiolabelled SN, dynamic and static images were performed and the skin projection of the detected SN was marked with a cobalt-57 source. For intra-operative mapping a hand-held gamma probe was used. Forty of the 83 respondents of the European-wide questionnaire (48%) performed the SN procedure. Although many different regimens are used, the following recommendations could be deduced for the SN procedure in patients with malignant melanoma and non-palpable LNs: (1) local, intradermal injection of 40 MBq 99mTc-nanocolloid around the diagnostic excision scar of the primary melanoma; (2) two-phase LS: dynamic imaging (20 frames of 60 s, 128x128 matrix, LEAP collimator) followed by static images 1-2 h later (180 s per record); (3) intra-operative retrieval of the SN with a gamma probe; (4) histopathological examination of the SN on serial sections. In our trial, surgical retrieval of the SN was successful in 95% of the cases. Dynamic lymphoscintigraphy (LS) contributed to the SN procedure by showing anatomically unpredictable lymph flow to extra-regional SNs (10% of the patients in this study) and multiple SNs. Of the 77 retrieved SNs, 13 contained metastatic disease (17%). Consequently, these patients underwent a formal LN dissection of the affected basin. In conclusion, the SN concept is a rational approach to select patients who could, theoretically, benefit from early LN dissection of the affected basin. Standardisation of the SN procedure will improve the results of this approach, and could be useful for quality control and for making comparisons with other countries in coming years.

Severe hepatic dysfunction after adenovirus-mediated transfer of the herpes simplex virus thymidine kinase gene and ganciclovir administration

The use of so-called 'suicide' genes to activate prodrugs has been effective in animal models for several solid tumor types and is now in phase I and II clinical trials. We have exploited adenovirus vectors (Ad) for transfer and expression of the herpes simplex virus thymidine kinase (HSVtk) gene to render rat colorectal liver metastases sensitive to the anti-herpetic agent ganciclovir (GCV). The efficacy and toxicity of this enzyme-prodrug combination were tested after in situ transduction of rat colorectal tumor cells and after intraportal administration of the vector Ad.CMV.TK. Our results demonstrate the validity of the approach but reveal that hepatic expression of HSVtk, both in tumor bearing and in tumor-free rats, provokes severe liver dysfunction and mortality upon GCV administration. These data show, that in contrast to the common assumption, normally non-mitotic tissues too, can be affected by adenovirus-mediated HSVtk transfer and subsequent GCV treatment. Given the hepatotropic nature of systemically administered adenovirus type 2- and 5-derived vectors, it will be essential to monitor liver functions of patients included in all gene therapy trials involving adenoviral vectors with the HSVtk gene.

Isolated hepatic perfusion with tumor necrosis factor alpha and melphalan: experimental studies in pigs and phase I data from humans

We report our experience with isolated hepatic perfusion (IHP) with tumor necrosis factor (TNF) and melphalan in an experimental pig study and of a phase I study in humans. IHP was performed with inflow catheters in the hepatic artery and portal vein and an outflow catheter in eh caval vein. An extracorporeal venovenous bypass was used. IHP consisted of a 60-min perfusion with hyperthermia (> 41 degrees C). For the pig protocol rhTNF alpha 50 micrograms/kg alone (n = 5) or rhTNF alpha 50 micrograms/kg plus melphalan 1 mg/kg (n = 3) were added. In two control pigs no drugs were added. In the phase I study, patients received melphalan 1 mg/kg with 0.4 mg rhTNF alpha (n = 8) or 0.8 mg rhTNF alpha (n = 1). After the perfusion the liver was washed with Macrodex before vascular continuity was restored. All pigs but one survived the procedure. Systemic leakage was less than 0.02%. Transient, mild liver toxicity was seen in all pigs, including controls, as demonstrated by liver enzyme assays and histology. There was no significant hemodynamic, cardiopulmonary hematological, or renal toxicity. In the phase I clinical study there was leakage in one patient (cumulative leakage 20%). There were three perioperative deaths (one possibly drug-related). All patients demonstrated significant hepatotoxicity. Survival ranged from 6 to 26 months (median 10.3 months). All patients demonstrated a tumor response (partial response 5/6, 1/6 stable disease) with a median duration of 18 weeks. In contrast to our pig program, many problems were encountered in the phase I study. By using both the hepatic artery and portal vein for IHP we encountered more toxicity than expected based on data from the pig program, resulting in fatal coagulative disturbances in one patient who received the second rhTNF alpha dose. Furthermore, local control after one IHP with TNF alpha and melphalan is only temporary.

Observations on initial cell loss after intraportal hepatocyte transplantation of 5'-bromo-deoxy-uridine-labeled hepatocytes

In the present study, attempts are made to improve posttransplant survival of intraportally transplanted hepatocytes in a syngeneic hepatocyte transplantation (HTX) model. Engrafted hepatocytes were detected and quantified after pretransplant labeling with 5'-bromo-deoxy-uridine. In order to enhance the survival percentage, three mechanisms that possibly influence cell survival were manipulated: (1) administration of Matrigel (extracellular-matrix components, Matrigel Basement Membrane Complex, Micronic BV, Lelystad, The Netherlands) in order to improve the environmental conditions of the transplanted hepatocytes; (2) immunosuppression of the recipients by 5 Gy total body irradiation and cyclosporin-A administration (25 mg/kg, 3 x weekly), and (3) Kupffer cell depletion by injection of dichloromethylene-diphosphonate-filled liposomes. The results were analyzed in relation to HTX without treatment. Cell survival was approximately 14% (10 days after HTX), and the transplanted hepatocytes were distributed equally throughout the various recipient liver lobes. However, no increase was attained by Matrigel coadministration, immunosuppression, or Kupffer cell depletion.

Blocking of alpha 1 beta 1 integrin strongly improves survival of hepatocytes in allogeneic transplantation

The survival rate of hepatocytes after allogeneic hepatocyte transplatation (HTX) is low, possibly because of formation of intravascular hepatocyte aggregates. The aim of this study was to determine the role of integrins in intravascular aggregation and intraparenchymal survival of transplanted hepatocytes in a fully allogeneic rat model. First, the expression profile of various integrins was determined on both isolated hepatocytes in vitro and on hepatocyte aggregates in recipient livers after intraportal transplantation of allogeneic hepatocytes. Next, the role of these integrins in hepatocyte aggregation was determined in an in vitro attachment assay on liver sections with function-blocking anti-integrin monoclonal antibodies (mAb). The results showed that anti-alpha 1 beta 1 integrin mAb significantly block hepatocyte attachment to vessel walls and liver parenchyma in vitro. Subsequently, the effect of preincubation of hepatocytes with anti-integrin mAb on their intravascular aggregation and on intraparenchymal survival was studied in an allogeneic HTX model. Preincubation with anti-leukocyte function-associated antigen-1 alpha or anti-beta 2 mAb significantly intravascular hepatocyte aggregation, and anti-leukocyte function-associated antigen-1 alpha mAb enhanced intraparenchymal survival. Preincubation with anti-alpha 1 or anti-beta 1 mAb did not inhibit aggregation but significantly improved survival from 2% to up to 45% at Day 2 after transplantation (p < 0.001). In conclusion, our results suggest that the blocking of alpha 1 beta 1 integrin significantly improves survival of allotransplanted hepatocytes.

[Towards safer and parenchyma-conserving liver resections: experience with three-dimensional reconstructions of spiral CT scan]

New techniques are available for the diagnosis and treatment of liver metastases. Three patients, a male aged 52 and two females aged 70 and 47, developed liver metastases after resection of a colorectal carcinoma. Spiral CT scanning made possible detailed three dimensional imaging of the liver to determine the extension of the metastases and the site of the metastasis in relation to blood vessels and bile ducts. This enabled the surgeon preoperatively to arrive at a balanced operation strategy, with the objectives of radical resection of the metastasis and conservation of sufficient residual liver tissue with minimal morbidity and mortality. In addition, use was made of peroperative clamping of blood vessels to determine the possibility of resecting along anatomical borders. This offers the advantages that less blood is lost and a smaller resection often suffices. In the 3 patients followed respectively a wedge excision of the tumour, a wedge excision combined with a hemihepatectomy and a resection of two segments.

Hepatic lesions: detection with ferumoxide-enhanced T1-weighted MR imaging

PURPOSE

To compare the use of ferumoxide-enhanced T1-weighted gradient-echo (GRE) MR imaging with that of spiral computed tomography during arterial portography (CTAP) and T2-weighted Turbo spin-echo (SE) MR imaging in detection of lesions and of segmental involvement in patients with liver metastases.

MATERIALS AND METHODS

Twenty-two candidates for metastasectomy of the liver underwent spiral CTAP, ferumoxide-enhanced GRE MR imaging, and T2-weighted Turbo SE MR imaging. A total of 176 liver segments were evaluated (57 with and 119 without metastases). The reference standard was laparoscopic sonographic findings. Diagnostic performance of the imaging modalities was assessed for lesion detection and determination of segmental involvement.

RESULTS

The sensitivity for lesion detection with spiral CTAP, ferumoxide-enhanced MR imaging, and T2-weighted MR imaging was 0.96, 0.83, and 0.71, respectively; for segmental analysis, the sensitivity was 0.96, 0.84, and 0.75, respectively, and the specificity was 0.80, 0.99, and 0.92, respectively. All comparisons between sensitivities and specificities were statistically significant (P < .05).

CONCLUSION

Ferumoxide-enhanced T1-weighted GRE MR imaging is superior to T2-weighted SE MR imaging for preoperative detection of lesions and segmental involvement in patients with liver metastases.

Monitoring engraftment of transplanted hepatocytes in recipient liver with 5-bromo-2'-deoxyuridine

For studies on the intrahepatic engraftment of transplanted hepatocytes, labeling of donor cells is necessary. Current labeling techniques enable only short-term monitoring of engraftment. In the present study, we describe the use of 5-bromo-2'-deoxyuridine (BrdU) for a more permanent hepatocyte labeling. BrdU is stably incorporated into replicating DNA; consequently, BrdU labeling was performed in regenerating livers. In 10 Lewis rats, a two-thirds partial hepatectomy was performed, followed by continuous, low-dose BrdU administration. This approach provided a fraction of 89+/-1.5% BrdU-labeled donor hepatocytes, without influencing the efficacy of the ensuing isolation of donor hepatocytes. Subsequently, +/-1 x 10(7) isolated hepatocytes were transplanted either intraportally or intrasplenically into syngeneic recipients, and the engraftment of transplanted cells was evaluated in liver lobes at successive time intervals after transplantation. BrdU-positive hepatocytes could be identified and quantitated in recipient livers up to 180 days after transplantation. Repetitive quantitative assessments over time revealed an initial, drastic loss of transplanted cells (<24 hr), followed by a stabilization at approximately 7% of the injected cells. Histological monitoring showed that during this period (<48 hr) the transplanted cells migrate from the portal venules to the liver parenchyma. In recipient livers a homogeneous lobe distribution of hepatocyte engraftment was found 30 days after both intraportal and intrasplenic transplantation. Moreover, no significant difference between the intrahepatic liver cell engraftment of the two transplantation routes was demonstrated. In conclusion, the BrdU-labeling technique of donor hepatocytes enables long-term histological monitoring and quantitative evaluation of the engraftment of transplanted liver cells in recipient livers.

The diagnostic accuracy of core biopsy in palpable and non-palpable breast lesions

OBJECTIVE

To assess the accuracy of large-core needle biopsy in evaluating palpable and nonpalpable breast lesions.

METHODS AND PATIENTS

Stereotaxic and ultrasound (US) guided core biopsies were performed in 103 breast lesions in 97 patients. Subsequently, all patients underwent surgery. All specimens (core biopsy and surgical) underwent radiography for evaluation of microcalcifications. The histopathologic findings of the core biopsies and the surgical specimens were correlated.

RESULTS

Core biopsies and surgery findings were concordant in 100% of the 27 palpable lesions and in 89% of the 76 nonpalpable lesions. One case of malignancy, ductal carcinoma in situ (DCIS), was not diagnosed by core biopsy. In 102 (99%) of the 103 breast lesions, a correct choice for additional diagnostic procedure or definitive treatment could have been made upon histopathologic findings of core biopsy.

CONCLUSION

Stereotaxic and ultrasound-guided core biopsy are safe, reliable and less traumatic than excisional biopsy. Special attention is necessary when atypical ductal hyperplasia (ADH) or DCIS without invasive carcinoma is found. Radiography of the biopsy specimens for detection of microcalcifications is essential.

Isolated hepatic perfusion in the pig with TNF-alpha with and without melphalan

Isolated limb perfusion with tumour necrosis factor alpha (TNF-alpha) and melphalan is well tolerated and highly effective in irresectable sarcoma and melanoma. No data are available on isolated hepatic perfusion (IHP) with these drugs for irresectable hepatic malignancies. This study was undertaken to assess the feasibility of such an approach by analysing hepatic and systemic toxicity of IHP with TNF-alpha with and without melphalan in pigs. Ten healthy pigs underwent IHP. After vascular isolation of the liver, inflow catheters were placed in the hepatic artery and portal vein, and an outflow catheter was placed in the inferior vena cava (IVC). An extracorporeal veno-venous bypass was used to shunt blood from the lower body and intestines to the heart. The liver was perfused for 60 min with (1) 50 microg kg(-1) TNF-alpha (n = 5), (2) 50 microg kg(-1) TNF-alpha plus 1 mg kg(-1) melphalan (n = 3) or (3) no drugs (n = 2). The liver was washed with macrodex before restoring vascular continuity. All but one pigs tolerated the procedure well. Stable perfusion was achieved in all animals with median perfusate TNF-alpha levels of 5.1 +/- 0.78 x 10(6) pg ml(-1) (+/- s.e.m). Systemic leakage of TNF-alpha from the perfusate was consistently < 0.02%. Following IHP, a transient elevation of systemic TNF-alpha levels was observed in groups 1 and 2 with a median peak level of 23 +/- 3 x 10(3) pg ml(-1) at 10 min after washout, which normalized within 6 h. No significant systemic toxicity was observed. Mild transient hepatotoxicity was seen to a similar extent in all animals, including controls. IHP with TNF-alpha with(out) melphalan in pigs is technically feasible, results in minimal systemic drug exposure and causes minor transient disturbances of liver biochemistry and histology.

Liver and tumour tissue concentrations of TNF-alpha in cancer patients treated with TNF-alpha and melphalan by isolated liver perfusion

In this study we determined the level of tumour necrosis factor alpha (TNF-alpha) in liver and tumour tissue samples obtained from patients with colorectal metastases confined to the liver, who were treated with isolated liver perfusion with TNF-alpha and melphalan. We adapted a standard enzyme-linked immunosorbent assay kit for the quantification of TNF-alpha in serum to measure the amount of this cytokine in solid tissue. For this purpose, we developed a buffer that lysed the tissues without affecting the TNF-alpha present. The minimum detection level was about 2 pg of TNF-alpha per mg tissue. Using this technique, we found a significant increase in the TNF-alpha level after perfusion in the liver tissue of all evaluable patients, which may explain the transient liver toxicity we observed in all patients. In tumour tissue, a significant TNF-alpha increase was observed in one out of five patients. The level of TNF-alpha in all liver tissue samples and some of the tumours after treatment by isolated liver perfusion was much higher than the peak serum concentrations obtained after systemic administration of the maximum tolerated dose of TNF-alpha. Furthermore, we demonstrated that the level of TNF-alpha in the liver tissue samples was about seven to eight times higher than in tumour tissue. We concluded that regional liver treatment resulted in a relatively high local level of TNF-alpha, but also that this cytokine did not preferentially accumulate in tumour tissue.

Gas explosion during colonic surgery

Explosions of the colon as a result of the use of diathermy in the presence of gas mixtures of oxygen, hydrogen and/or methane have been previously described in the literature. This danger is present during colonoscopic polypectomy as well as during colonic surgery. The following case is presented to alert to the potential hazards of bowel gas during electrosurgery.

Correction of an inborn error of metabolism by intraportal hepatocyte transplantation in a dog model

The aims of this study were (1) to assess portal hemodynamics during intraportal hepatocyte transplantation (HTX) in dogs, (2) to evaluate a new method for the detection of transplanted hepatocytes using 5-bromo-2'-deoxyuridine (BrdU) incorporation, and (3) to determine the metabolic effects of HTX on an inborn error of the purine metabolism in dalmatian dogs. HTX was performed by intraportal infusion of freshly isolated allogeneic beagle hepatocytes. Portal flow and pressure were monitored continuously during HTX. For the detection experiments, beagles received hepatocytes that had been exposed to BrdU during regeneration of the donor liver, induced by partial hepatectomy. For metabolic studies, dalmatian dogs were used as recipients. Repetitive HTX was performed. As judged by the portal hemodynamics, the number of hepatocytes that could be infused safely varied from 5 x 1O(8) to 8 x 1O(8) in beagles, to 1 x 10(9) in dalmatians. Transaminase levels showed a 5- to 6-fold increase (P=0.05) after HTX, but normalized within 3 weeks. BrdU-positive cells were identified in the recipient livers 2 weeks after HTX and 5-10% of the total amount of transplanted hepatocytes was retrieved. A significant (P=0.05) decrease in serum uric acid was demonstrated after repeated HTX in dalmatians. In conclusion, (1) intraportal HTX is feasible, but portal hypertension limits the maximum amount of hepatocytes that can be infused in one HTX; (2) BrdU labeling is an attractive method for the detection of transplanted hepatocytes in the recipient liver; and (3) after two consecutive hepatocyte transplantations, a temporary correction of the purine metabolism was accomplished in the dalmatian dog.

[Initial results of immediate reconstruction of the breast following mastectomy]

OBJECTIVE

Evaluation of the results of immediate reconstruction after mastectomy for breast cancer by means of a silicone implant.

DESIGN

Retrospective analysis.

SETTING

Department of Surgical Oncology of the Dr Daniël den Hoed Cancer Centre and Department of Surgery of the Zuiderziekenhuis, Rotterdam, the Netherlands.

METHOD

From September 1990 till July 1993, 37 immediate reconstructions of the breast after mastectomy were performed in 35 patients by means of a silicone implant. Indications for the treatment, consequences for further oncological treatment, additional plastic surgery, and complications of the reconstruction were evaluated.

RESULTS

The indications for mastectomy and immediate reconstruction were local recurrence after breast conservative treatment (6 operations), multifocal disease (8), extensive in situ carcinoma (8), non-radically removed tumour at lumpectomy (5), anticipated poor cosmetics after breast conservative treatment (6), prophylactic ablation of the breast (2), and patient preference (1). 5 patients received adjuvant systemic chemotherapy, which could be administered without delay, and without negative influence on the result of the breast reconstruction. Additional plastic surgical treatment consisting of reconstruction of the areolar complex and correction of the breast symmetry, was performed in 5 and 3 patients respectively. In 8 of the 37 reconstructions (22%) complications were encountered. The main complications were haematoma (2), infection (4), implant removal (3), capsular contracture (2), skin necrosis (2), and luxation of the implant (1).

CONCLUSION

Immediate reconstruction after mastectomy is a valuable treatment modality in breast cancer.

Proliferative response of hepatocytes transplanted into spleen or solid support

Understanding the regenerative behavior of transplanted hepatocytes is of great importance for developing and improving such novel therapeutic strategies as hepatocellular transplantation and ex vivo gene therapy. In this study the proliferative responsiveness of transplanted syngeneic rat hepatocytes was examined in relation to the timing of the administration of a mitogenic stimulus. For this purpose nuclear bromodeoxyuridine incorporation after partial hepatectomy was investigated during the early post-transplant phase. The response of intrasplenically transplanted hepatocytes was compared to that of liver cells engrafted in polytetrafluoroethylene solid supports that had been implanted intraperitoneally 4 weeks prior to transplantation. Nonstimulated, engrafted hepatocytes exhibited a labeling index of approximately 0-1% independent of the transplantation technique used. This "spontaneous" labeling index did not change with time. Partial hepatectomy, executed simultaneously with hepatocyte transplantation through either technique, did not result in significant alteration of this proliferation index. Delayed kinetics were found not to be responsible for this lack of responsiveness. When the mitogenic stimulus was given between 2 and 6 weeks post-transplantation, a significant increase in labeling index was observed in comparison to sham-treated control animals. Maximal labeling indices of approximately 3-4% were found if the stimulus took place at 4 weeks post-transplantation. Both the pattern and the extent of the proliferative response seen in liver cells engrafted in solid supports were similar to the ones found in intrasplenic hepatocytes, indicating adequate vascularization of the supports. This data provides the first description of proliferative response in hepatocytes transplanted by the solid support technique, which may offer an attractive alternative to the intrasplenic route.(ABSTRACT TRUNCATED AT 250 WORDS)

An extracorporeal microscopy perfusion chamber for on-line studies of environmental effects on cultured hepatocytes

The development of bioartificial-hybrid organ support systems is hampered by the lack of knowledge on the effects of different (in vivo) environments on cells during extracorporeal perfusion. In the present study, a perfusion chamber was designed for continuous monitoring of cultured cells during perfusion with media, as well as during plasma perfusion in an extracorporeal circuit. Chamber characterization showed satisfactory thermal and perfusion profiles and no major pH fluctuations. Further testing was performed with hepatocytes that were cultured in between two collagen layers, a configuration which was previously shown to preserve hepatocyte morphology and function for over six weeks of culture. Perfusion of the hepatocytes with culture media did not adversely affect cell morphology and function, provided the perfusion time was < or = 48 hours. Perfusion of the cultures during connection of the chamber to an extracorporeal circuit involving normal rats for six hours resulted in reversible cytoplasmic changes, unaltered cell shapes indices, and a 40 percent increase in albumin secretion rate during the first post-perfusion day, followed by a return to stable control levels. We expect that this chamber will be a valuable tool for on-line studies of cells under (extracorporeal) perfusion conditions and could be used for a large variety of studies on regeneration, reperfusion damage, and detoxification.

Nucleation and growth of ice crystals inside cultured hepatocytes during freezing in the presence of dimethyl sulfoxide

A three-part, coupled model of cell dehydration, nucleation, and crystal growth was used to study intracellular ice formation (IIF) in cultured hepatocytes frozen in the presence of dimethyl sulfoxide (DMSO). Heterogeneous nucleation temperatures were predicted as a function of DMSO concentration and were in good agreement with experimental data. Simulated freezing protocols correctly predicted and explained experimentally observed effects of cooling rate, warming rate, and storage temperature on hepatocyte function. For cells cooled to -40 degrees C, no IIF occurred for cooling rates less than 10 degrees C/min. IIF did occur at faster cooling rates, and the predicted volume of intracellular ice increased with increasing cooling rate. Cells cooled at 5 degrees C/min to -80 degrees C were shown to undergo nucleation at -46.8 degrees C, with the consequence that storage temperatures above this value resulted in high viability independent of warming rate, whereas colder storage temperatures resulted in cell injury for slow warming rates. Cell damage correlated positively with predicted intracellular ice volume, and an upper limit for the critical ice content was estimated to be 3.7% of the isotonic water content. The power of the model was limited by difficulties in estimating the cytosol viscosity and membrane permeability as functions of DMSO concentration at low temperatures.

Retroviral infection and expression of cationic amino acid transporters in rodent hepatocytes

The susceptibility of rodent hepatocytes to infection by mouse type C retroviruses was examined in vivo and in vitro and compared with the expression of two membrane proteins that function as transporters for the cationic amino acids CAT-1 and CAT-2. CAT-1 expression in rodents determines susceptibility to ecotropic retrovirus infection by serving as the virus receptor. Recently, it has been suggested that CAT-2 may be a receptor for amphotropic murine leukemia virus. In the present study, CAT-1 expression was observed in Hepa1, a cell line derived from a murine hepatoma, and in rat hepatocytes propagated on collagen monolayers in vitro but not in intact or regenerating rat liver in vivo. The expression of CAT-1 correlated with susceptibility to infection by an ecotropic retrovirus encoding beta-galactosidase. CAT-2 expression was observed in hepatocytes in vitro and in vivo, consistent with reports of infection of regenerating and cultured hepatocytes by amphotropic retroviruses. However, introduction of murine CAT-2 into nonpermissive Chinese hamster cells was not sufficient to confer susceptibility to amphotropic retrovirus infection, using a protocol that could easily demonstrate CAT-1-dependent infection by an ecotropic virus. Our data establish CAT-1 as a major determinant of ecotropic retrovirus infection in rodent hepatocytes and suggest that CAT-2 is not a receptor for viruses in the amphotropic subgroup.

A stable long-term hepatocyte culture system for studies of physiologic processes: cytokine stimulation of the acute phase response in rat and human hepatocytes

Prior studies on the in vitro hepatic acute phase response have involved either hepatoma cell lines or conventional short-term cultures of primary hepatocytes. No data are available on the response of primary hepatocytes in stable long-term culture systems. In this study, the acute phase response of rat and human hepatocytes in a new long-term culture system was examined in response to interleukin-6 (IL-6), interleukin-1 beta (IL-1 beta), and tumor necrosis factor alpha (TNF-alpha). The cultured cells were sandwiched between two layers of collagen in a (double-gel) configuration which has been shown to preserve both hepatocyte function and morphology over prolonged periods of time. The stability of this culture configuration enabled us to investigate, for the first time, the temporal aspects of the response in addition to the effects of the mediators on protein secretion. Exposure of rat hepatocytes to IL-6 after culture for 16 days resulted in a 2-fold reduction of albumin secretion and a 15-fold increase in the secretion rates of fibrinogen and alpha 2-macroglobulin. In all instances, the peak response occurred at 48 h after IL-6 exposure, and all protein secretion rates returned to pretreatment values within 5 days posttreatment. Changes in the mRNA levels of these proteins in response to IL-6 corresponded with those changes seen with the secreted products, indicating pretranslational regulation. Administration of IL-1 beta to rat hepatocyte produced a similar decline of albumin secretion and a 5-fold increase of fibrinogen secretion, whereas alpha 2-macroglobulin secretion remained undisturbed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of dimethyl sulfoxide on cultured rat hepatocytes in sandwich configuration

A recently developed sandwich culture system, in which hepatocytes are sandwiched between two layers of collagen, has been shown to be capable of maintaining long-term expression of hepatocellular function (J. C. Y. Dunn et al., Biotechnol. Prog. 7, 237-245, 1991). The development of an adequate technique for the cryopreservation of hepatocytes in such a stable culture configuration would ensure a ready supply of hepatocytes for use in bioreactors or bioartificial liver support devices. This report describes the effects of exposing hepatocytes in sandwich culture to different concentrations of the cryoprotectant dimethyl sulfoxide (Me2SO) at 22 degrees C on Day 7 of culture. Cell function, morphology, and cytoskeletal organization were followed for 14 days after exposure. Hepatocellular morphology and albumin secretion remained normal when cultures were exposed for up to 120 min to predicted final Me2SO concentrations up to 1.33 M. Exposure for less than 60 min to equilibrium concentrations of up to 3.33 M Me2SO did not adversely affect cell morphology or albumin secretion rate, but at the highest concentration (3.33 M), increase of the exposure time to 60 or 120 min resulted in dramatic, irreversible cell damage and loss of function. Actin filament organization was shown to be undisturbed when the cells were exposed to 1.33 M Me2SO for 60 min, but was irreversibly disrupted by exposure to 3.33 M for 120 min. Based on these results, a simple and safe procedure is suggested for the addition of Me2SO to hepatocytes in a sandwich culture configuration and its subsequent removal, which will be valuable for studies on hepatocyte cryopreservation.

Does auxiliary heterotopic liver transplantation reverse hypersplenism and portal hypertension?

In this study, performed to assess the effect of auxiliary heterotopic liver transplantation on portal hypertension and hypersplenism, eight patients with chronic liver disease who underwent the procedure and had functioning grafts for at least 6 months were analyzed. The transplantation resulted in (a) normalization of platelet and leukocyte counts, (b) reduction of splenomegaly by 20% +/- 3% (P less than 0.02), (c) disappearance of ascites, and (d) diminution of esophageal varices in all patients. Intraoperatively, the mean portacaval pressure gradient decreased with 54% +/- 7% after recirculation of the graft (P less than 0.05). In conclusion, a functioning auxiliary heterotopic liver graft decompresses portal hypertension and reverses hypersplenism.

Treatment of manifest and impending pathologic fractures of the femoral neck by cemented hemiarthroplasty

Thirty-four patients with manifest or impending pathologic fractures of the femoral neck were treated between 1971 and 1987. Breast carcinoma was the primary tumor in the majority of patients. All patients were treated with cemented hemiarthroplasty. Twenty-seven patients (79%) could walk at an average of nine days postoperatively. All patients experienced relief of pain. Two superficial wound dehiscences, one loosening of the prosthesis, and two prosthetic dislocations were encountered. Mean survival was 17.6 months overall (12 months for manifest fractures and 40 months for impending fractures). These results indicate that cemented hemiarthroplasty for pathologic fractures is a safe procedure resulting in long-lasting palliation without necessitating postoperative irradiation. The importance of tumor excochleation and the advantages of bone cement are emphasized.